As the technology relating to the processing of video data and graphics data continues to advance, multimedia applications have become more and more in demand from a consumer perspective. Information of various interests to the consumers can be presented in different formats on different media. Information can be presented in a text format, a graphics format, an audio format, and a video format, etc. Different format standards as well as various industry standards have been developed with respect to the creation, transmission, processing, and presentation of information to the users.
The once separate domains of computer industry and television industry are coming together in their efforts to explore new ways to make information available to the consumers in a more convenient, efficient and cost-effective manner. Traditionally, only composite video signals from either an analog video source or a digital video source can be displayed on a television screen. The consumers, however, may have a need to access other information in other data formats, for example, graphics, while watching their television programs. Moreover, the consumers may want to be more than just passive viewers. They may want to be able to turn their television system into a workstation to perform various other tasks while watching TV or use their television as a device to communicate and interact with other entities, e.g., service providers, etc. In other words, the consumers may want their television system to be interactive. More particularly, the consumers may want to be able to retrieve information in different formats while watching TV, order items or services from service providers, participate in on-line programs, send email, etc., through interactions with their television system.
To enable the consumers to use their television set or any display processing device as an interactive tool to perform the various tasks and functions mentioned above, there exists a need to combine the information in different formats/media from different sources such as video data, graphics data, etc. into some common format and present such information to the users according to some display arrangement or configuration. More specifically, to enable the users to use their television system as an interactive device that functions as both a television and a computer, it is necessary to combine video data, graphics data, etc. and display the output data as composite images on the television screen with some mechanism to allow the users to interact with their television, for example, using a cursor to select or activate various options presented on the screen.